If you're on a console, make sure your games are patched to the highest one, however your console does its updates.

Caveat: You can skip this step for now and only do it as a last resort. The last couple of patches have introduced a couple of bugs.. although the 1.05 patch for Dragon Age: Origins is necessary to fix the bug with DLC not authenticating properly. It's up to you, but the Keep team wants both games to be updated to the latest patch for the best experience trying to sync.